1. Field of the Invention
The present invention relates to a method of logging faults in memory in an electronic controlled internal combustion engine having an electronic control unit with memory.
The present invention further relates to a method of filtering data signals through a debounce logic to filter erroneous fault signals.
2. Description of Related Art
Young U.S. Pat. No. 6,157,671 discloses a circuit for digitally monitoring a duty cycle of a pulse width modulated signal. The circuit includes s counter portion, a digital filter, and a data storage device. The counter portion is connectable to receive the pulse width modulated signal and is operable to monitor the pulse width modulated signal for a predetermined time period during which account value is established. The digital filter is connected to receive the count value established by the counter portion and is also connected to receive a stored count value from the storage device, the digital filter being operable to establish a filtered count value based upon the count value and the stored count value input thereto. The storage device is connected to receive the filtered count value established by the digital filter. Multiple pwm signals may also be monitored by including multiple counters, multiple storages devices, and one or more multiplexers.
Downs U.S. Pat. No. 6,492,818 discloses an apparatus for determining component fault conditions associated with a capacitive discharge ignition system for an internal combustion engines and includes a number of AC coupling circuits connected to a spark detection circuit, wherein the combination is responsive to a corresponding number of primary coil voltage signals to produce digital pulses indicative of recorded spark events from various secondary coils in the respective primary coils of the ignition system. A number of level shifting circuits are also included and provide a pulse width circuit with a corresponding number of level-shifted primary coil voltage signals. A pulse width circuit is responsive to the number of level-shifted primary coil voltage signals to produce appropriate digital pulses time d to match the non-zero voltage times of the various primary coil voltage signals. A voltage processing circuit is responsive to the digital signals produced by the spark detection circuit and the pulse width circuit to determine spark breakdown voltage, shorted ignition coils, worn ignition plugs, shorted ignition plugs, ignition control module faults and external arcing conditions. These faults are communicated to a service technician via a display and/or by logging such faults in memory.
Kendrick et al. U.S. Pat. No. 6,810,366 discloses apparatuses and methods for filtering a signal. A first processing device receives a first control signal and a first feedback signal and transmits a first error signal as a function of those signals. A second processing device receives the first error signal and transmits a second control signal as a function of the first error signal, a deadband, and a gain factor. A third processing device receives the second control signal and the first feedback signal and transmits an output signal as a function of those signals. A fourth processing device receives the out signal and transmits the first feedback signal as a function of the output signal to the first processing device and the third processing device, the first feedback signal being substantially equal to the output signal delayed by a first predetermined duration of time.